[storm] Update branch format for trunk?

[James Henstridge]

Currently the Storm trunk is stored in the old pack-0.92 format that
dates back to the Bazaar 1.0 release.  We've got a few branches
tracking storm stored in the newer "2a" format (made default in Bazaar
2.0), and I was wondering if anyone would object to changing the trunk
to the newer format.

My main reason for asking this is that changes can only be moved in
one direction between these formats (i.e. we can pull pack-0.92
changes, but nothing can go in the other direction).  So moving the
trunk forward would reduce the chance that I'd need to redo commits in
order to create a mergeable branch.

It would also have some direct benefits, since Launchpad can handle
the newer branches better by stacking them on the trunk branch..  In
other words, uploading a new branch will only upload the changes you
made rather than Storm's entire history (which is currently ~ 3.5MB).

The obvious down side is that if we upgrade the trunk, everyone else
will need to upgrade their branches if they want to pull new changes
from trunk.  They will also need to make sure they have Bazaar 2.0 or
later.

So what do others think?

James.